The head of a Congolese satirical weekly has been arrested for libel, a journalists' union said Wednesday, weeks ahead of polls in which President Denis Sassou Nguesso will seek re-election.

Raymond Malonga, editor of Sel-Piment (Salt and Pepper), "was arrested yesterday... because he had supposedly libelled the wife of a senior official," Union of Press Professionals in Congo (UPPC) president Jean-Charles Maniongui told AFP.

Maniongui said 60-year-old Malonga's detention was "an attempt to muzzle the press" before the March 21 presidential poll in the Republic of Congo, also called Congo-Brazzaville.

"We're in the process of gathering all the documents to determine whether or not our colleague is guilty," the press union chief added.

The online weekly, known for stories critical of the government, was suspended several weeks ago by the High Council for Freedom of Communication (CSLC) -- led by a former minister from Sassou Nguesso's PCT party.

Congo was ranked 118th out of 180 countries in Reporters Without Borders' global Press Freedom Index last year.

President Sassou Nguesso, 77, who has ruled for a total of 36 years, faces little opposition in the upcoming vote as the main opposition Pan-African Union for Social Democracy (UPADS) has said it will boycott the polls.

Meanwhile the country's Catholic bishops have warned the ballot may not be free and fair given coronavirus restrictions and issues with the electoral system.

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